SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e9d2bb83b2b2f5908f5dc1299de3469fe57a159bdc9dea8fa375ffb1b2b8a016' 
  AND token = 'CX1Dxfx1irjrYvz+kgAvFEA+V/jJtVh4GQkmx05JAig=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}